Iron and Steel bridges are used today and most of the
worlds major rivers are crossed by this type. The picture shows the first
iron bridge in the world. It was built in Telford in 1779 by Abraham Darby
(the third) and was the first large structure in history to be constructed
from iron. It revolutionised the way structures were built enabling
engineers to build ever larger structures and buildings.

MODERN STEEL BRIDGES

Girder bridges often carry railways
and many were built in the early part of the 20th century.
They are capable of carrying heavy weights. Usually they span short
distances.

The Humber Bridge was once the longest suspension
bridge in the world. Suspension bridges are the cheapest way of spanning
long distances. Cables hold the road in position.

A cantilever bridge has a deck (road) which is
supported at one end.

The Forth Railway Bridge in Queensferry, Scotland is made up of three cantilevers. It
was finished in 1890 and took eight years to build.

QUESTIONS

What is the name of the city
where this bridge is to be found ?

Find it on a globe of the world or in an atlas.

What is the name of the city where this bridge is to be
found ? Two famous towers are to be seen on the right - they no longer
exist.